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In: Mechanical Engineering

# Hot water from a boiler of power plant are discharged through a 0.2-m-diameter, thin-walled pipe with...

Hot water from a boiler of power plant are discharged through a 0.2-m-diameter, thin-walled pipe with a velocity of 3.5 m/s. The pipe passes through a room whose air temperature is 3°C and the exterior surface of the pipe is uninsulated and pipe length is 30 m.

(a) At a position in the pipe where the mean water temperature is 40°C, determine the heat loss and the pipe wall temperature.

(b) If the pipe is covered with a 20-mm-thick layer of insulation (k = 0.5 W/m K) what are the pipe wall temperature, the outer surface temperature, and the heat loss?

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